On The Lab's blog: Designing for Receipt Printers

I wrote a bit for the office blog about our work writing HTML and CSS that ends
up printed on a bit of paper a couple of inches wide:

For web developers, there’s no real technical challenge in the front-end
side of creating a publication; it’s all HTML and CSS with nothing to think
about other than how WebKit will render your page in black and white. But
this lack of difficulty is more than made up for with the tough constraints
imposed by the media and the size it’ll be printed at. The printable area is
less than 400 pixels wide and just 800 tall to avoid the unpleasant surprise
of waking up to a publication five metres long trailing across the floor.
Berg’s guidelines recommend that text should be sized no smaller than 20px
(and they’re dead on), but with letters so large and paper so small there
isn’t room to say much.